Communications comprising a plurality of access technologies have received great interest. Well known examples are dual mode telephones such as DECT/GSM phones and GSM/WCDMA phones. DECT (Digital Enhanced Cordless Telephone) is a radio access technology, RAT, applying Gaussian Minimum Shift Keying, GMSK, combining 10 carriers of frequency division multiplex, FDM, and 12 slots of time division multiplex, TDM, for each of uplink and downlink directions applying time division duplex, TDD, sending uplink and downlink communications separated in time. GSM (Global System for Mobile Communications) also applies GMSK, FDM and TDM but, in contrast to DECT, applies frequency division duplex, FDD, sending communications in uplink and downlink directions on different frequencies. WCDMA (Wideband Code Division Multiple Access) also separates uplink and downlink directions in frequency in FDD-mode of UMTS, applying code division multiple access for multi-user access.
Ouyang Congxing, Wang Bin, Wang Xiaoqi, Wei Bing and Huang Yuhong, ‘An analysis of radio handover success ratio,’ Huawei Technologies, November 2005, Issue 19, analyzes factors that may affect handover success ratio with inter-RAT handover. The inter-RAT handover includes the steps of                1. Measurement;        2. Judgement; and        3. Implementation.        
The Measurement step teaches about signal level, signal quality and synchronization information of target RAT. In the Judgement step, the Measurement results are reported to the source side, or source RAT. The source side or the terminal may determine on whether or not to actually handover to the target RAT. In the latter case, the terminal will directly establish the connection with the target side wireless system cell. In the former case, the source side notifies the target side to prepare the corresponding channel resource and then the source side system issues the handover command to notify the terminal to transfer to the target side wireless system. The authors conclude that network planning will be crucial, including settings of proper handover judgment thresholds and handover delay time. A fast fading signal at the target side is a primary reason for inter-RAT handover failure.
Eva Gustafsson, Annika Jonsson, ‘Always Best Connected,’ IEEE Wireless Communications, February 2003, describes the concept of Always Best Connected, ABC. The paper discusses user experience and business relationships to broaden third generation cellular systems, 3G, such as Universal Mobile Telecommunications System (UMTS) or CDMA2000. The fundamentals of the ABC concept are that a user shall always be connected through the best available device and access technology at all times. The definition of best, the B in ABC, depends on a number of different aspects such as personal preferences, size and capabilities of the device, application requirements, security, operator or corporate policies, available network resources and network coverage. Depending on the applications and user preferences, a user can be connected over one access at a time or over multiple accesses in parallel. The ABC concept holds for virtually all types of access technologies including those that are yet to come. In its simplest form, an ABC service provides the user with capabilities to access services of different types of network technologies, without mobility support. Gustafsson and Jonsson describe example scenarios of a user named Hubert. In one scenario Hubert has a PDA (Personal Digital Assistant) and a laptop, both of which have built-in 3G capabilities. In another scenario the laptop and the PDA are part of Hubert's personal area network, PAN, communicating over short-range radio technology, e.g. Bluetooth. In the example, the PAN also includes Hubert's 3G mobile phone. An ABC terminal may be inclusive or exclusive of access devices. In the former case, the terminal performs access discovery periodically and at startup to find out the best available access technology. In the latter case, the access discovery is an internal functionality of the device as long as there is only one device. When there is a plurality of devices including access devices connected in a PAN, the ABC terminal needs to find out which access devices are available in the PAN. Key issues for providing ABC access discovery for a PAN are:                Defining a generic set of parameters describing access networks and devices. Examples of such parameters are type of access network technology, access network operator, QoS (Quality of Service), current cost for a particular user to connect over a particular network, type of access device, and type of connectivity the access device can offer;        Investigating how the statistics of the access networks should be collected, e.g. in terms of measurements, information from operators and so on;        In a PAN, handling the dynamics of the PAN in terms of access devices becoming available or unavailable as the PAN configuration changes.        
Access selection refers to the process of deciding over which access network to connect at any point in time. Gustafsson and Jonsson identify three parts of such a process:                1. Terminal-based selection;        2. Network-based selection; and        3. User intervention.        
When selecting access network, a number of different aspects are considered, such as ABC user preferences, service provider preferences, available bandwidth, cost and operator, device capabilities and application requirements. An ABC terminal needs a stored profile or priority list, or default setting for choosing access network at startup or reconnection. Otherwise, it cannot benefit from any network-based functionality. A benefit of network-based support for access selection, or network-based access selection is that an ABC service provider could transfer network-specific information to the terminal. Network-based access selection allows for load balancing, and may reduce signaling over the radio interface if the selection process requires repeated inquiries to databases in the network. Network-based support for access selection makes it possible to perform radio-resource-efficient selection in order to maximize total system throughput.
Gustafsson and Jonsson describe different approaches for content adaptation.                1. One approach is for an application to detect changes in network characteristics and/or device capabilities and request the application server to adapt the contents accordingly.        2. A second approach is for the terminal to provide information about the access network and device to either of the application, the application server, or databases and servers in the ABC service provider network.        3. A third approach is to let the access network provide information to the application server and/or the device regarding network characteristics (e.g., notification of QoS changes).        
Bo Xing and Nalini Venkatasubramanian, ‘Multi-Constraint Dynamic Access Selection in Always Best Connected Networks,’ Proc. of The Second Annual Int. Conf. on Mobile and Ubiquitous Systems: Networking and Services, Volume 00, 2005, Jul. 17-21, 2005, pp. 56-64, addresses the problem of dynamic access selection, the concept of ABC enabling a new paradigm in fourth generation mobile communication, 4G, systems. The authors model the problem of multi-constraint dynamic access selection, MCDAS, as a variant of bin packing problem. A series of approximation algorithms derived from the First Fit Decreasing, FFD, algorithm are proposed for finding near-optimal solutions in access selection comprising various access technologies, such as Wi-Fi, Bluetooth, GPRS and UMTS, simultaneously available to mobile devices.
The optimizations incorporate the ability to adapt to varying load conditions as well as dynamic network parameter changes caused by device mobility. The proposed algorithms are compared to a quasi-optimal off-line solution, obtained assuming full knowledge of all traffic flows for a set of inputs.
Access preference of a flow describes which access network is preferred by a traffic flow and to which extent. A power consumption cost model calculates the power consumption of a particular flow, fi, using a particular access network, Aj. A dissatisfaction value of each traffic flow assignment describes the degree to which the assignment does not match the flow's access preference.
A bin packing problem, packing items into smallest number of bins of given maximum size, is called on-line if every item is packed without information on subsequent items, while an off-line problem allows decisions to be made with full knowledge of all items.
FFD is a well-known algorithm for off-line packing items in bins, of given maximum size packing the largest item into the first bin which has enough remaining room, when the bins are ordered in sequence of decreasing fill-level (increasing remaining room).
G. P. Koudouridis, P. Karlsson, J. Lundsjö, A. Bria, M. Berg, L. Jorguseski, M. Meago, R. Agüero, J. Sachs., R. Karimi, ‘Multi-Radio Access in Ambient Networks,’ IST EVEREST Workshop, Barcelona, Spain, November 2005, illustrates multi-radio access, MRA, for addressing the dynamics of ambient networks, ANs. Accessing any network, public or private, possibly without subscription, through instant establishment of inter-network agreements is one of the strategic objectives of The Ambient Networks project, an integrated project within The EU 1st 6th Framework Program. Koudouridis et al. provide an overview of evaluation studies for multi-radio access selection, MRAS, in terms of efficient radio resource utilization.
For radio access selection, Koudouridis et al. propose a hierarchical distribution of functionality between multi-radio resource management, MRRM, and generic link layer, GLL, where the GLL dynamically handles mapping of data flows to radio accesses, RAs, selected by MRRM. The criteria used for selection of access include: radio link characteristics, cell load and capacity, RAT preferences, terminal capabilities, terminal velocity, service type and required QoS. Multi-radio transmission diversity, MRTD, essentially refers to system capability of selecting on a relatively fine time-scale among plural radio accesses for transmission of user data. Ultimately, MRTD selects radio access on a per packet basis.
None of the cited documents above discloses a method and system of access selection with flow bundling constraints, the access selection determining and including one or more metrics in an access preference list of a Communications Flow Correlation Module.